Display substrate, manufacturing method thereof, and display device

ABSTRACT

A display substrate, a manufacturing method thereof, and a display device are provided. The display substrate includes: a base substrate; an anode structure, disposed on the base substrate; a light emitting layer, disposed on a side of the anode structure away from the base substrate; and a cathode layer, disposed on a side of the light emitting layer away from the base substrate, the anode structure includes a reflective layer and an inorganic layer disposed on a side of the reflective layer away from the base substrate, the cathode layer includes a transflective layer, and the inorganic layer is configured to adjust a distance between the reflective layer and the transflective layer.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. Ser. No. 16/063,951 filed onJun. 19, 2018, which is a national stage application of internationalapplication PCT/CN2017/112927 filed on Sep. 24, 2017, which claimspriority from China Patent application No. 201710373488.6 filed on May24, 2017, the disclosures of all of these applications herebyincorporated herein by reference in their entirety.

TECHNICAL FIELD

Embodiments of the present disclosure relate to a display substrate, amanufacturing method thereof, and a display device.

BACKGROUND

Organic Light Emitting Diode (OLED) display devices have become aresearch hotspot due to their advantages such as self-luminescence, highcontrast, thin thickness, wide viewing angle, fast response speed,flexibility, and wide operating temperature range.

In addition, with the continuous development of wearable technology,micro display devices have a vast market application space. For example,a micro display device can be used to a helmet display device, aglasses-type display, and the like. The micro display device can obtainaccurate image information at anywhere and anytime by linking togetherwith mobile communication networks, satellite positioning system, or thelike, thereby having a relatively wide application prospect.

SUMMARY

At least one embodiment of the present disclosure provides a displaysubstrate, which includes: a base substrate; an anode structure,disposed on the base substrate; a light emitting layer, disposed on aside of the anode structure away from the base substrate; and a cathodelayer, disposed on a side of the light emitting layer away from the basesubstrate, the anode structure includes a reflective layer and aninorganic layer disposed on a side of the reflective layer away from thebase substrate, the cathode layer includes a transflective layer, andthe inorganic layer is configured to adjust a distance between thereflective layer and the transflective layer.

For example, in the display substrate provided by an example of thepresent embodiment, the distance between the reflective layer and thetransflective layer satisfies: D=j(λ/2n), wherein D is the distancebetween the reflective layer and the transflective layer, λ is awavelength of light of a predetermined color, and n is an effectiverefraction index of a medium between the reflective layer and thetransflective layer, and j is a positive integer.

For example, in the display substrate provided by an example of thepresent embodiment, the anode structure includes a first anodestructure, a second anode structure, and a third anode structure, whichare disposed on the base substrate at intervals, the first anodestructure includes a first reflective layer and a first inorganic layerdisposed on the first reflective layer, the second anode structureincludes a second reflective layer and a second inorganic layer disposedon the second reflective layer, the third anode structure includes athird reflective layer and a third inorganic layer disposed on the thirdreflective layer, and the first inorganic layer, the second inorganiclayer, and the third inorganic layer have different thicknesses.

For example, in the display substrate provided by an example of thepresent embodiment, the display substrate includes a plurality of subpixels, and the plurality of sub pixels are disposed in a one-to-onecorrespondence with the first to third anode structures, and the subpixel corresponding to the first anode structure is configured to emitlight of a first color, the sub pixel corresponding to the second anodestructure is configured to emit light of a second color, and the subpixel corresponding to the third anode structure is configured to emitlight of a third color; a wavelength of light of the first color is λ1,a wavelength of light of the second color is λ2, and a wavelength oflight of the third color is λ3; a distance D1 between the firstreflective layer of the first anode structure and the transflectivelayer, a distance D2 between the second reflective layer of the secondanode structure and the transflective layer, and a distance D3 betweenthe third reflective layer of the third anode structure and thetransflective layer satisfy: D1=j₁(λ₁/2n), D2=j₂(λ₂/2n) andD3=j₃(λ₃/2n), wherein n is an effective refraction index of a mediumbetween the reflective layer and the transflective layer, and j₁, j₂,and j₃ are positive integers.

For example, in the display substrate provided by an example of thepresent embodiment, j₁=1, j₂=2, and j₃=3.

For example, the display substrate provided by an example of the presentembodiment further includes: a color filter layer, disposed on a side ofthe cathode layer away from the base substrate, wherein the color filterlayer includes a first color filter block having a first color, a secondcolor filter block having a second color, and a third color filter blockhaving a third color, the first color filter block, the second colorfilter block, and the third color filter block respectively correspondto the first anode structure, the second anode structure, and the thirdanode structure.

For example, in the display substrate provided by an example of thepresent embodiment, the light emitting layer and the cathode layer eachare disposed on an entirety of the first anode structure, the secondanode structure, and the third anode structure.

For example, in the display substrate provided by an example of thepresent embodiment, the inorganic layer is further configured to protectthe reflective layer.

For example, in the display substrate provided by an example of thepresent embodiment, a material of the inorganic layer includesmolybdenum oxide or titanium nitride.

At least one embodiment of the present disclosure provides amanufacturing method of a display substrate, including: forming an anodestructure on a base substrate, the anode structure including areflective layer and an inorganic layer disposed on a side of thereflective layer away from the base substrate; forming a light emittinglayer on a side of the anode structure away from the base substrate; andforming a cathode layer on a side of the light emitting layer away fromthe base substrate, the cathode layer includes a transflective layer,and the inorganic layer is configured to adjust a distance between thereflective layer and the transflective layer.

For example, in the manufacturing method of a display substrate providedby an example of the present embodiment, forming the anode structure onthe base substrate includes: forming the reflective layer on the basesubstrate by a patterning process; and forming the inorganic layer on aside of the reflective layer away from the base substrate by apatterning process, an orthographic projection of the inorganic layer onthe base substrate is completely overlapped with an orthographicprojection of the reflective layer on the base substrate.

For example, in the manufacturing method of a display substrate providedby an example of the present embodiment, forming the anode structure onthe base substrate includes: forming a first anode structure, a secondanode structure and a third anode structure which are disposed on thebase substrate at intervals, the first anode structure includes a firstreflective layer and a first inorganic layer disposed on the firstreflective layer, the second anode structure includes a secondreflective layer and a second inorganic layer disposed on the secondreflective layer, the third anode structure includes a third reflectivelayer and a third inorganic layer disposed on the third reflectivelayer, and the first inorganic layer, the second inorganic layer, andthe third inorganic layer have different thicknesses.

For example, in the manufacturing method of a display substrate providedby an example of the present embodiment, forming the first anodestructure, the second anode structure and the third anode structure onthe base substrate includes: forming the first reflective layer, thesecond reflective layer, and the third reflective layer on the basesubstrate by a patterning process.

For example, in the manufacturing method of a display substrate providedby an example of the present embodiment, forming the first anodestructure, the second anode structure and the third anode structure onthe base substrate further includes: forming a first sub inorganic layeron a side of the first reflective layer, the second reflective layer andthe third reflective layer away from the base substrate; forming a firstphotoresist pattern on a side of the first sub inorganic layer away fromthe base substrate, wherein the first photoresist pattern covers thefirst reflective layer and gaps among the first reflective layer, thesecond reflective layer, and the third reflective layer, and exposes thesecond reflective layer and the third reflective layer; forming a secondsub inorganic layer on the first photoresist pattern and the first subinorganic layer; forming a second photoresist pattern on a side of thesecond sub inorganic layer away from the base substrate, wherein thesecond photoresist pattern covers the first reflective layer, the thirdreflective layer, and the gaps among the first reflective layer, thesecond reflective layer, and the third reflective layer; forming a thirdsub inorganic layer on the second photoresist pattern and the second subinorganic layer; and removing the first photoresist pattern and thesecond photoresist pattern through a development, wherein the firstinorganic layer includes the first sub inorganic layer, the secondinorganic layer includes the first sub inorganic layer, the secondinorganic layer, and the third inorganic layer, the third inorganiclayer includes the first sub inorganic layer and the second subinorganic layer.

For example, in the manufacturing method of a display substrate providedby an example of the present embodiment, forming the first sub inorganiclayer on a side of the first reflective layer, the second reflectivelayer and the third reflective layer away from the base substrateincludes: forming an inorganic material layer on a side of the firstreflective layer, the second reflective layer and the third reflectivelayer away from the base substrate; and patterning the inorganicmaterial layer to form the first sub inorganic layer, an orthographicprojection of the first sub inorganic layer on the base substrate iscompletely overlapped with an orthographic projection of the firstreflective layer, the second reflective layer, and the third reflectivelayer on the base substrate.

For example, in the manufacturing method of a display substrate providedby an example of the present embodiment, a material of the reflectivelayer includes aluminum or silver.

For example, in the manufacturing method of a display substrate providedby an example of the present embodiment, a material of the inorganiclayer includes molybdenum oxide or titanium nitride.

At least one embodiment of the present disclosure provides a displaydevice, including the any one of the abovementioned display substrates.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to clearly illustrate the technical solution of embodiments ofthe present disclosure, the drawings of the embodiments will be brieflydescribed in the following, it is obvious that the drawings in thedescription are only related to some embodiments of the presentdisclosure and not limited to the present disclosure.

FIG. 1 is a schematic structural diagram of a display substrate;

FIG. 2 is a schematic structural diagram of a display substrate providedby an embodiment of the present disclosure;

FIG. 3 is a schematic structural diagram of another display substrateprovided by an embodiment of the present disclosure;

FIG. 4 is a flow diagram of a manufacturing method of a displaysubstrate provided by an embodiment of the present disclosure; and

FIGS. 5a-5g are schematic diagrams of steps of a manufacturing method ofa display substrate provided by an embodiment of the present disclosure.

DETAILED DESCRIPTION

In order to make objects, technical details and advantages of theembodiments of the disclosure apparent, the technical solutions of theembodiments will be described in a clearly and fully understandable wayin connection with the drawings related to the embodiments of thedisclosure. Apparently, the described embodiments are just a part butnot all of the embodiments of the disclosure. Based on the describedembodiments herein, those skilled in the art can obtain otherembodiment(s), without any inventive work, which should be within thescope of the disclosure.

Unless otherwise defined, all the technical and scientific terms usedherein have the same meanings as commonly understood by one of ordinaryskill in the art to which the present disclosure belongs. The terms“first,” “second,” etc., which are used in the present disclosure, arenot intended to indicate any sequence, amount or importance, butdistinguish various components. Also, the terms “comprise,”“comprising,” “include,” “including,” etc., are intended to specify thatthe elements or the objects stated before these terms encompass theelements or the objects and equivalents thereof listed after theseterms, but do not preclude the other elements or objects. “Connected”and “connecting” and the similar terms are not limited to physical ormechanical connection, and they also include electrical connection,direct connection or indirect connection.

Organic Light Emitting Diode (OLED) display devices occupy an importantposition in micro display device filed due to their unique advantages.Due to the limitation of Fine Metal Mask (FMM), conventional OLEDdisplay device cannot achieve high PPI (Pixel Per Inch). Therefore, uponan OLED display device being used as a micro display device, the OLEDdisplay adopts a structure of white light+color film. FIG. 1 is aschematic structural diagram of an OLED display device adopting astructure of white light+color film. As illustrated by FIG. 1, the OLEDdisplay device includes a base substrate 10, an anode 20 disposed on thebase substrate 10, a hole injection layer 30 disposed on a side of theanode 20 away from the base substrate 10, and a hole transport layer 40disposed on a side of the hole injection layer 30 away from the basesubstrate 10, an organic light emitting layer 50 disposed on a side ofthe hole transport layer 40 away from the base substrate 10, an electrontransport layer 60 disposed on a side of the organic light emittinglayer 50 away from the base substrate 10, a cathode 70 disposed on aside of the electron transport layer 60 away from the base substrate 10,an encapsulation layer 80 disposed on a side of the cathode 70 away fromthe base substrate 10, and a color filter layer 90 disposed on a side ofthe encapsulation layer 80 away from the base substrate 10. The organiclight emitting layer 50 can emit white light, for example, the organiclight emitting layer 50 can include a first sub organic light emittinglayer 51 emitting orange-red light and a second sub organic lightemitting layer 52 emitting blue-green light. The color filter layer 90can include a plurality of color filter blocks having different colors,such as a color filter block having red color, a color filter blockhaving green color, and a color filter block having blue color, and thecolor filter blocks are disposed in a one-to-one correspondence with theanodes, so that white light emitted from the organic light emittinglayer 50 can display color after being filtered by the color filterlayer 90. Because the anode and the color filter blocks can bemanufactured through a mask process, the OLED display device can achievea relatively high PPI. However, the color gamut of the abovementionedOLED display adopting the structure of white light+color film isreduced.

Embodiments of the present disclosure provide a display substrate, amanufacturing method of the same, and a display device. The displaysubstrate includes a base substrate, an anode structure provided on thebase substrate, a light emitting layer provided on a side of the anodestructure away from the base substrate, and a cathode layer provided ona side of the light emitting layer far from the base substrate. Theanode structure includes a reflective layer and an inorganic layerdisposed on a side of the reflective layer away from the substrate. Thecathode layer includes a transflective layer, and the inorganic layer isconfigured to adjust the distance between the reflective layer and thetransflective layer. Thus, the reflective layer and the transflectivelayer can constitute a micro cavity effect structure, and the distancebetween the reflective layer and the transflective layer can be adjustedby an additional inorganic layer, thereby narrowing the luminescencespectrum of the sub pixel corresponding to the anode structure, so as tofurther improve the color purity.

Hereinafter, the display substrate, the manufacturing method thereof,and the display device provided by embodiments of the present disclosurewill be described with reference to the accompanying drawings.

An embodiment of the present disclosure provides a display substrate.FIG. 2 is a schematic structural diagram of a display substrateaccording to the present embodiment. As illustrated by FIG. 2, thedisplay substrate includes a base substrate 101, an anode structure 110disposed on the base substrate 101, a light emitting layer 140 disposedon a side of the anode structure 110 away from the base substrate 101,and a cathode layer 180 disposed at a side of the light emitting layer140 away from the base substrate 101. The anode structure 110 includes areflective layer 111 and an inorganic layer 112 disposed on a side ofthe reflective layer 111 away from the base substrate 101; the cathodelayer 180 includes a transflective layer 181. For example, asillustrated by FIG. 2, the cathode layer 180 itself can be thetransflective layer. The inorganic layer 112 can adjust the distancebetween the reflective layer 111 and the transflective layer 181. Itshould be noted that the cathode layer itself can be a transflectivelayer, or can be additionally provided with a transflective layer, theembodiments of the present disclosure are not limited thereto. Inaddition, the abovementioned reflective layer can be an anode in ananode structure, or can be a reflective layer which is additionallyprovided on the anode. In a case where the reflective layer is an anodein an anode structure, the anode can be made of a metallic material suchas silver or aluminum. In addition, the light emitting layer can be anorganic light emitting layer.

In the display substrate provided in the present embodiment, thereflective layer in the anode structure and the transflective layer inthe cathode layer can constitute a micro cavity effect structure, andthe light emitting layer disposed between the anode structure and thecathode layer can be electroluminescent. The light directly emitted bythe light emitting layer and the light reflected by the reflective layercan interfere with each other in the abovementioned micro cavity effectstructure; light with a specific wavelength or a specific wavelengthrange can enhanced by adjusting the distance between the reflectivelayer and the transflective layer through the inorganic layer which isadditionally provided, and light with other wavelengths is weakened, sothat the luminescence spectrum of the sub pixel corresponding to theanode structure can be narrowed, thereby improving the color purity.Upon the display substrate provided in the present embodiment beingapplied to an OLED display device having a structure of white light plusa color filter, the color gamut of the OLED display can be improvedunder the premise of having a relatively high PPI by increasing thecolor purity of every sub pixels.

For example, in the display substrate provided in an example of thepresent embodiment, the distance between the reflective layer and thetransflective layer satisfies a following formula: D=j(λ/2n), where D isthe distance between the reflective layer and the transflective layer, λis a wavelength of light of a predetermined color, n is an effectiverefractive index of a medium between the reflective layer and thetransflective layer, and j is a positive integer. It should be notedthat: the effective refractive index of the medium between thereflective layer and the transflective layer refers to an effectiverefractive index of the layer medium (e.g., an organic layer, an organiclight emitting layer, and a hole transport layer, etc.) between thereflective layer and the transflective layer. Thus, the displaysubstrate can adjust the distance between the reflective layer and thetransflective layer by adjusting the thickness of the additionallyprovided inorganic layer to make the distance between the reflectivelayer and the transflective layer satisfy the abovementioned formula;such that light of a predetermined color is enhanced while the light ofother colors is weakened, thereby improving the color purity. It shouldbe noted that: the effective refractive index of the medium between thereflective layer and the transflective layer refers to an effectiverefractive index of the layers (e.g., an organic layer, an organic lightemitting layer, and a hole transport layer, etc.) serving as an entiretybetween the reflective layer and the transflective layer. For example,the effective refractive index can be measured experimentally orcalculated.

For example, supposing that the medium between the reflective layer andthe transflective layer includes four layer structures whose thicknessand refractive index respectively are respectively d1, n1; d2, n2; d3,n3; d4, n4, and the effective refractive index of the medium between thereflective layer and transflective layer can be equal to(d1·n1+d2·n2+d3·n3+d4·n4)/(d1+d2+d3+d4).

For example, the predetermined color can be red, green or blue; ofcourse, embodiments of the present disclosure include but are notlimited thereto.

For example, in the display substrate provided in an example of thepresent embodiment, as illustrated by FIG. 2, the anode structure caninclude a first anode structure 1101, a second anode structure 1102, anda third anode structure 1103; the first anode structure 1101, the secondanode structure 1102, and the third anode structure 1103 which aredisposed on the base substrate 101 at intervals. The first anodestructure 1101 includes a first reflective layer 1111 and a firstinorganic layer 1121 disposed on a side of the first reflective layer1111 away from the base substrate 101: the second anode structure 1102includes a second reflective layer 1112 and a second inorganic layer1122 disposed on a side of the second reflective layer 1112 away fromthe base substrate 101; the third anode structure 1103 includes a thirdreflective layer 1113 and a third inorganic layer 1123 disposed at aside of the third reflective layer 1113 away from the base substrate101; and the thicknesses of the first inorganic layer 1121, the secondinorganic layer 1122, and the third inorganic layer 1123 are different.Therefore, the sub pixels corresponding to the first anode structure,the second anode structure, and the third anode structure canrespectively emit different light with higher color purity, so that theOLED display device using the display substrate has a relatively highcolor gamut.

For example, in the display substrate provided by an example of thepresent embodiment, as illustrated by FIG. 2, the display substrateincludes a plurality of sub pixels 300. The plurality of sub pixels 300are disposed in one-to-one correspondence with the anode structures 110,and the sub pixel corresponding to the first anode structure 1101 isconfigured to emit light of a first color, the sub pixel correspondingto the second anode structure 1102 is configured to emit light of asecond color, and the sub pixel corresponding to the third anodestructure 1103 is configured to emit light of a third color. Thewavelength of the light of the first color is λ₁, the wavelength of thelight of the second color is λ₂, and the wavelength of the light of thethird color is λ₃, the distance between the first reflective layer ofthe first anode structure and the transflective layer is D1, thedistance between the second reflective layer of the second anodestructure and the transflective layer is D2, and the distance betweenthe third reflective layer of the third anode structure and thetransflective layer is D3 respectively satisfy: D1=j₁(λ₁/2n),D2=j₂(λ₂/2n) and D3=j₃(λ₃/2n), where n is the effective refractive indexof the medium between the reflective layer and the transflective layer,and j₁, j₂, and j₃ are positive integers.

For example, the sub pixel corresponding to the first anode structureemits red light with high color purity, the sub pixel corresponding tothe second anode structure emits green light with high color purity, andthe sub pixel corresponding to the third anode structure emits bluelight with high color purity.

For example, in a sub pixel corresponding to the first anode structure,the distance between the first reflective layer and the transflectivelayer can satisfy the following formula: D1=j₁(λ₁/2n), where D1 is thedistance between the first reflective layer and the transflective layer,is the wavelength of red light, n is the effective refractive index ofthe medium between the first reflective layer and the transflectivelayer, and j₁ is a positive integer. Thus, the sub pixel correspondingto the first anode structure emits red light with high color purity.

For example, the wavelength of red light can be selected to be 620 nm.The effective refractive index of the medium between the firstreflective layer and the transflective layer can be selected to be 1.8,and D1 can be calculated to be 172 j₁ nanometers.

For example, in the sub pixel corresponding to the second anodestructure, the distance between the second reflective layer and thetransflective layer can satisfy the following formula: D2=j₂(λ₂/2n), D2is the distance between the second reflective layer and thetransflective layer, λ₂ is the wavelength of green light, n is theeffective refractive index of the medium between the second reflectivelayer and the transflective layer, and j₂ is a positive integer. Thus,the sub pixel corresponding to the second anode structure emits greenlight with high color purity.

For example, the wavelength of red light can be selected to be 520 nm,and the effective refractive index of the medium between the firstreflective layer and the transflective layer can be selected to be 1.8,and D2 can be calculated as 144 j₂ nm.

For example, in the sub pixel corresponding to the third anodestructure, the distance between the third reflective layer and thetransflective layer can satisfy the following formula: D3=j₃(λ₃/2n),wherein, D3 is the distance between the third reflective layer and thetransflective layer, λ₃ is the wavelength of blue light, n is theeffective refractive index of the medium between the third reflectivelayer and the transflective layer, and j₃ is a positive integer. Thus,the sub pixel corresponding to the third anode structure emits bluelight with high color purity.

For example, the wavelength of red light can be selected to be 460 nm,and the effective refractive index of the medium between the firstreflective layer and the transflective layer can be selected to be 1.8,and D3 can be calculated as 127 j₃ nm.

For example, in the display substrate provided by an example of thepresent embodiment, as illustrated by FIG. 2, the display substratefurther includes a color filter layer 190 disposed on a side of thecathode layer 180 away from the base substrate 101. The color filterlayer 190 includes a first color filter block 191 having a first color(e.g., red color), a second color filter block 192 having a second color(e.g., green color), and a third color filter block 193 having a thirdcolor (e.g., blue color). The first color filter block 191, the secondcolor filter block 192, and the third color filter block 193 arerespectively disposed corresponding to the first anode structure 1101,the second anode structure 1102, and the third anode structure 1103.Therefore, the first color filter block can filter out the light emittedby the light emitting layer corresponding to the first anode structureexcept the light of the first color, the second color filter block canfilter out the light emitted by the light emitting layer correspondingto the second anode structure except the light of the second color, andthe third color filter block can filter out the light emitted by thelight emitting layer corresponding to the third anode structure exceptthe light of the third color, thereby further enhancing the color purityof the sub pixels respectively corresponding to the first, second, andthird anode structures. It should be noted that the color filter layercan be provided or not provided, and the embodiment of the presentdisclosure is not limited thereto.

For example, in the display substrate provided in an example of thepresent embodiment, as illustrated by FIG. 2, the light emitting layer140 and the cathode layer 180 are continuously disposed on the firstanode structure 1101, the second anode structure 1102, and the thirdanode structure 1103, respectively. That is, the light emitting layer140 and the cathode layer 180 are disposed on an entirety of the firstanode structure 1101, the second anode structure 1102, and the thirdanode structure 1103. Thus, the light emitting layer 140 can be directlyformed by using an open mask instead of using a fine metal mask (FMM).On the one hand, the display substrate does not need to be formed byusing a fine metal mask (FMM), which saves costs; on the other hand, thePPI of the display substrate is also relatively high.

For example, as illustrated by FIG. 2, the light emitting layer 140includes a first sub light emitting layer 141 and a second sub lightemitting layer 142. The first sub light emitting layer 141 can emitorange-red light through electroluminescence, and the second sub lightemitting layer 142 can emit blue-green light throughelectroluminescence. Thus, the entire light emitting layer emits whitelight. Of course, the embodiments of the present disclosure include, butare not limited thereto, and the light emitting layer can also be otherstructures as long as white light can be emitted. For example, the lightemitting layer can include three sub light emitting layers that emit redlight, green light, and blue light, respectively.

For example, in the display substrate provided in an example of thepresent embodiment, as illustrated by FIG. 2, the inorganic layer 112 isdisposed on the side of the reflective layer 111 away from the basesubstrate 101. The inorganic layer 112 can also serve as a protectivelayer of the reflective layer 111 for protecting the reflective layer.

For example, in the display substrate provided in an example of thepresent embodiment, molybdenum oxide can be used as the material of theinorganic layer. On the one hand, molybdenum oxide is convenient foretching and patterning; on the other hand, molybdenum oxide can also beused as a hole injection layer, so that an additional hole injectionlayer is not need to be provided.

For example, as illustrated by FIG. 2, the display substrate furtherincludes an encapsulation layer 185 disposed between the cathode layer180 and the color filter layer 190 for adhering the color filter layer190 to the display substrate.

FIG. 3 is a schematic structural diagram of another display substrateaccording to the present embodiment. As illustrated by FIG. 3, thedisplay substrate further includes an electron stop layer 120 disposedbetween the anode structure 110 and the light emitting layer 140 forblocking electrons, thereby improving the stability of the displaysubstrate.

For example, as illustrated by FIG. 3, the display substrate furtherincludes a hole transport layer 130 disposed between the electron stoplayer 120 and the light emitting layer 140 for transporting holes to thelight emitting layer.

For example, as illustrated by FIG. 3, the display substrate furtherincludes a hole stop layer 150 and an electron transport layer 160disposed between the light emitting layer 140 and the cathode layer 180.

For example, in the display substrate provided in an example of thepresent embodiment, the electron stop layer, the hole transport layer,the hole stop layer, and the electron transport layer can becontinuously disposed on the first anode structure, the second anodestructure, and the third anode structure, respectively. That is, theelectron stop layer, the hole transport layer, the hole stop layer, andthe electron transport layer can be disposed on an entirety of the firstanode structure, the second anode structure, and the third anodestructure. As a result, the electron stop layer, the hole transportlayer, the hole stop layer, and the electron transport layer can bedirectly formed by using an open mask without using a fine metal mask(FMM). On the one hand, the display substrate does not need to bemanufactured by using a fine metal mask (FMM), which saves costs; on theother hand, the PPI of the display substrate is also relatively high.

An embodiment of the present disclosure provides a manufacturing methodof a display substrate. FIG. 4 is a flow diagram of a manufacturingmethod of a display substrate according to the present embodiment. Asillustrated by FIG. 4, the manufacturing method of the display substrateincludes the following steps S201 to S203.

Step S201: forming an anode structure on a base substrate, the anodestructure including a reflective layer and an inorganic layer disposedon a side of the reflective layer away from the base substrate.

For example, the base substrate can employ a glass substrate, a quartzsubstrate, a plastic substrate, or other substrates.

Step S202: forming a light emitting layer on a side of the anodestructure away from the base substrate.

For example, the light emitting layer can be an organicelectroluminescent layer, and can include a plurality of sub lightemitting layers, such as an orange-red light emitting layer and ablue-green light emitting layer, so as to emit white light.

Step S203: forming a cathode layer on a side of the light emitting layeraway from the base substrate, the cathode layer includes a transflectivelayer, and the inorganic layer can adjust the distance between thereflective layer and the transflective layer.

For example, the cathode layer itself can be a transflective layer, orcan be additionally provided with a transflective layer. The embodimentsof the disclosure are not limited thereto.

In the manufacturing method of the display substrate provided in thepresent embodiment, the reflective layer in the anode structure formedon the base substrate and the transflective layer in the cathode layercan constitute a micro cavity effect structure, and the light emittinglayer disposed between the anode structure and the cathode layer can beelectroluminescent. The light directly emitted by the light emittinglayer and the light reflected by the reflective layer can interfere witheach other in the abovementioned micro cavity effect structure; lightwith a specific wavelength or a specific wavelength range can enhancedby adjusting the distance between the reflective layer and thetransflective layer through the inorganic layer which is additionallyprovided, and light with other wavelengths is weakened, so that theluminescence spectrum of the sub pixel corresponding to the anodestructure can be narrowed, thereby improving the color purity. Inaddition, because the light emitting layer can be used for emittingwhite light in the manufacturing method provided by the presentembodiment, the light emitting layer can be manufactured only by an openmask, without using a fine metal mask (FMM), thereby saving theprocesses and reducing the costs.

For example, in the manufacturing method of a display substrate providedin an example of the present embodiment, the step S201 of forming ananode structure on a base substrate can include: forming a reflectivelayer on the base substrate by using a patterning process; and formingan inorganic layer on a side of the reflective layer away from the basesubstrate by using a patterning process, and an orthographic projectionof the inorganic layer on the base substrate is completely overlappedwith an orthographic projection of the reflective layer on the basesubstrate. Therefore, layers of the anode structure can be manufacturedby using a mask process instead of a fine metal mask (FMM). Therefore,the number or density of the anode structures per unit area isrelatively high, so that the display substrate manufactured by themanufacturing method provided by the present embodiment has a relativelyhigh PPI. It should be noted that the abovementioned patterning processcan be a masking process or a printing process, and the masking processcan include steps of exposing, developing, etching, and the like.

For example, the reflective layer can be formed on the base substrate byusing a sputtering process and a dry etching process.

For example, in the manufacturing method of a display substrate providedin an example of the present embodiment, forming an anode structure on abase substrate can include: forming a first anode structure, a secondanode structure, and a third anode structure which are disposed on thebase substrate at intervals, the first anode structure includes a firstreflective layer and a first inorganic layer disposed on the firstreflective layer, the second anode structure includes a secondreflective layer and a second inorganic layer disposed on the secondreflective layer, and the third anode structure includes a thirdreflective layer and a third inorganic layer disposed on the thirdreflective layer. The first inorganic layer, the second inorganic layer,and the third inorganic layer have different thicknesses. Therefore, thesub pixels corresponding to the first anode structure, the second anodestructure, and the third anode structure can respectively emit differentlight with relatively high color purity, so that the display substratemanufactured by the manufacturing method of the display substrateprovided by the present embodiment has a relatively high color gamut.

For example, FIGS. 5a-5g are schematic diagrams of steps of amanufacturing method of a display substrate according to the presentembodiment. As illustrated by FIG. 5a , in the manufacturing method of adisplay substrate provided in an example of the present embodiment,forming a first anode structure, a second anode structure, and a thirdanode structure on the base substrate includes: using a patterningprocess to form a first reflective layer 1111, a second reflective layer1112, and a third reflective layer 1113 on the base substrate 101.Therefore, each of the reflective layers can be manufactured by using amask process instead of a fine metal mask (FMM). Therefore, the numberor density of the reflective layers per unit area is relatively high, sothat the display substrate manufactured by the manufacturing methodprovided by the present embodiment has a relatively high PPI. It shouldbe noted that: the first reflective layer, the second reflective layer,and the third reflective layer described above can also serve as thefirst anode, the second anode, and the third anode.

For example, in the manufacturing method of a display substrate providedin an example of the present embodiment, As illustrated by FIGS. 5b-5g ,forming the first, second, and third anode structures on a basesubstrate further includes: as illustrated by FIG. 5b , forming a firstsub inorganic layer 171 on a side of the first reflective layer 1111,the second reflective layer 1112, and the third reflective layer 1113away from the base substrate 101. As illustrated by FIG. 5c , forming afirst photoresist pattern 210 on a side of the first sub inorganic layer171 away from the base substrate 101, and the first photoresist layer210 covers the first reflective layer 1111 and gaps among the firstreflective layer 1111, the second reflective layer 1112, and the thirdreflective layer 1113, and exposes the second reflective layer 1112 andthe third reflective layer 1113; as illustrated by FIG. 5d , forming asecond sub inorganic layer 172 on the first photoresist pattern 210 andthe first sub inorganic layer 171; as illustrated by FIG. 5e , forming asecond photoresist pattern 220 on a side of the second sub inorganiclayer 172 away from the base substrate 101, the second photoresistpattern 220 covers the first reflective layer 1111, the third reflectivelayer 1113, and the gaps among the first reflective layer 1111, thesecond reflective layer 1112, and the third reflective layer 1113; asillustrated by FIG. 5f , forming a third sub inorganic layer 173 on thesecond photoresist pattern 220 and the second sub inorganic layer 172;as illustrated by FIG. 5g , removing the first photoresist pattern 210and the second photoresist pattern 220 through a development, andremoving a part of the second sub inorganic layer 172 and a part of thethird sub inorganic layer 173 which are located directly above the firstphotoresist pattern 210 and the second photoresist pattern 220. In thissituation, the first inorganic layer is the first sub inorganic layer171, the second inorganic layer includes the first sub inorganic layer171, the second inorganic layer 172, and the third inorganic layer 173,and the third inorganic layer includes the first sub inorganic layer 171and the second sub inorganic layer 172. As a result, the first inorganiclayer, the second inorganic layer, and the third inorganic layer havingdifferent thicknesses can be formed. It should be noted that, asillustrated by FIGS. 5c-5f , the first photoresist pattern 210 can alsobe filled in the gaps between the first reflective layer 1111, thesecond reflective layer 1112 and the third reflective layer 1113, andthe second photoresist pattern 220 can also be filled in the gapsbetween the first reflective layer 1111, the second reflective layer1112, and the third reflective layer 1113. Certainly, embodiments of thepresent disclosure include, but are not limited thereto, a pixeldefining layer can be firstly formed among the first reflective layer,the second reflective layer, and the third reflective layer, and thenthe first photoresist pattern and the second photoresist pattern can beformed.

For example, in a case where the distance between the first reflectivelayer and the transflective layer is 172 j₁ nanometers, the distancebetween the second reflective layer and the transflective layer is 144j₂ nanometers, and the distance between the third reflective layer andthe transflective layer is 127 j₃ nanometers. Because the distancebetween the first reflective layer and the transflective layer is 172 j₁nm, which is relatively large, the distance between the first reflectivelayer and the transflective layer can be applied as the first period,that is, j₁=1; the distance between the second reflective layer and thetransflective layer and the distance between the third reflective layerand the transflective layer are relatively small, they can be applied asthe second period, that is, j₂=2 and j₃=3. If the thickness of otherlayers (for example, the electron stop layer, the hole transport layer,the light emitting layer, the hole stop layer, and the electrontransport layer) except the inorganic layer between the reflective layerand the transflective layer is 160 nm, then it can be calculated thatthe thickness of the first inorganic layer is 12 nm, the thickness ofthe second inorganic layer is 94 nm, and the thickness of the thirdinorganic layer is 120 nm. Thus, the thickness of the first subinorganic layer is 12 nanometers, the thickness of the second subinorganic layer is 82 nanometers, and the thickness of the third subinorganic layer is 26 nanometers.

For example, in the manufacturing method of a display substrate providedin an example of the present embodiment, forming the first sub inorganiclayer on a side of the first reflective layer, the second reflectivelayer, and the third reflective layer away from the base substrateincludes: forming an inorganic material layer on a side of thereflective layer, the second reflective layer, and the third reflectivelayer away from the base substrate; and patterning the inorganicmaterial layer to form a first sub inorganic layer, and an orthographicprojection of the first sub inorganic layer on the base substrate iscompletely overlapped with an orthographic projection of the firstreflective layer, the second reflective layer, and the third reflectivelayer on the base substrate.

For example, in the manufacturing method of a display substrate providedin an example of the present embodiment, the material of the reflectivelayer includes aluminum or silver. Thus, the reflective layer can alsoserve as a reflective layer as well as an anode.

For example, in the manufacturing method of a display substrate providedin an example of the present embodiment, the material of the inorganiclayer includes molybdenum oxide or titanium nitride. On the one hand,molybdenum oxide is convenient for etching and patterning; on the otherhand, molybdenum oxide can also be used as a hole injection layer, sothat an additional hole injection layer can be not provided.

An embodiment of the present disclosure provides a display deviceincluding the display substrate described in any one of theabovementioned embodiments. Therefore, the display device can have ahigh color gamut under the premise of guaranteeing a relatively highPPI.

For example, the display device can be a micro display device such as ahelmet display device and a glasses-type display device. Certainly,embodiments of the present disclosure include, but are not limitedthereto, and the display device can also be an electronic device havinga display function, such as: a notebook computer, a navigator, atelevision, a mobile phone, or the like.

The following points should to be explained:

(1) The accompanying drawings involve only the structure(s) inconnection with the embodiment(s) of the present disclosure, and otherstructure(s) can be referred to common design(s).

(2) In the absence of conflict, the features of the same embodiment andthe different embodiments can be combined with each other.

The foregoing is only the embodiments of the present invention and notintended to limit the scope of protection of the present invention,alternations or replacements which can be easily envisaged by anyskilled person being familiar with the present technical field shallfall into the protection scope of the present disclosure. Thus, theprotection scope of the present disclosure should be based on theprotection scope of the claims.

What is claimed is:
 1. A display substrate, comprising: a basesubstrate; an anode structure, disposed on the base substrate,comprising a first anode structure, a second anode structure and a thirdanode structure; an organic light emitting layer, disposed on a side ofthe anode structure away from the base substrate; a cathode layer,disposed on a side of the organic light emitting layer away from thebase substrate, a color filter layer, disposed on a side of the cathodelayer away from the base substrate, wherein the color filter layercomprises a first filter block of red color, a second filter block ofgreen color and a third filter block of blue color, the first filterblock, the second filter block and the third filter block are disposedrespectively corresponding to the first anode structure, the secondanode structure and the third anode structure; wherein the anodestructure comprises a reflective layer, and a distance between thereflective layer in the second anode structure and the organic lightemitting layer is greater than a distance between the reflective layerin the first anode structure and the organic light emitting layer. 2.The display substrate according to claim 1, wherein an inorganic layeris between the reflective layer and the organic light emitting layer. 3.The display substrate according to claim 2, wherein the inorganic layercomprises a layer having a hole injection function.
 4. The displaysubstrate according to claim 2, wherein a total thickness of theinorganic layer between the reflective layer in the second anodestructure and the organic light emitting layer is greater than a totalthickness of the reflective layer.
 5. The display substrate according toclaim 1, wherein the organic light emitting layer is a continuous layer.6. The display substrate according to claim 1, wherein the organic lightemitting layer comprises a first sub organic light emitting layer and asecond sub organic light emitting layer, and the first sub organic lightemitting layer and the second sub organic light emitting layer areconfigured to emit light of different colors.
 7. The display substrateaccording to claim 1, wherein the organic light emitting layer isconfigured to emit white light.
 8. The display substrate according toclaim 1, wherein at the second anode structure, the organic lightemitting layer comprises a first slope part and a second slope part atedges of the second anode structure and comprises a flat part betweenthe first slope part and the second slope part, and a slope angle of thefirst slope part and a slope angle of the second slope part aredifferent at a same horizontal plane.
 9. The display substrate accordingto claim 1, wherein an encapsulation layer is between the color filterlayer and the organic light emitting layer, a distance H2 between asurface, close to the organic light emitting layer, of the encapsulationlayer corresponding to the second anode structure and the reflectivelayer is greater than a distance H1 between a surface, close to theorganic light emitting layer, of the encapsulation layer correspondingto the first anode structure and the reflective layer.
 10. The displaysubstrate according to claim 1, wherein a distance between thereflective layer in the second anode structure and the cathode layer isgreater than a distance between the reflective layer in the first anodestructure and the cathode layer.
 11. The display substrate according toclaim 1, wherein a material of the reflective layer comprises aluminum;and a material of the inorganic layer comprises titanium element. 12.The display substrate according to claim 2, wherein a material of theinorganic layer comprises molybdenum oxide or titanium nitride.
 13. Thedisplay substrate according to claim 2, wherein a layer count of theinorganic layer is more than one, and a layer count of the cathode layeris more than one.
 14. The display substrate according to claim 2,wherein the inorganic layer comprises a first sub inorganic layer, asecond sub inorganic layer and a third sub inorganic layer.
 15. Adisplay substrate, comprising: a base substrate; an anode structure,disposed on the base substrate, comprising a first anode structure, asecond anode structure and a third anode structure; an organic lightemitting layer, disposed on a side of the anode structure away from thebase substrate; a cathode layer, disposed on a side of the organic lightemitting layer away from the base substrate, a color filter layer,disposed on a side of the cathode layer away from the base substrate,wherein the color filter layer comprises a first filter block, a secondfilter block and a third filter block, the first filter block, thesecond filter block and the third filter block are disposed respectivelycorresponding to the first anode structure, the second anode structureand the third anode structure; wherein at the second anode structure,the organic light emitting layer comprises a first slope part and asecond slope part at edges of the second anode structure and comprises aflat part between the first slope part and the second slope part, and aslope angle of the first slope part and a slope angle of the secondslope part are different at a same horizontal plane.
 16. The displaysubstrate according to claim 15, wherein the first filter block is a redfilter block, the second filter block is a green filter block, and thethird filter block is a blue filter block.
 17. The display substrateaccording to claim 15, wherein a distance between the first slope partand the base substrate gradually decreases in a direction away from theflat part.
 18. The display substrate according to claim 15, wherein adistance between the second slope part and the base substrate graduallydecreases in a direction away from the flat part.
 19. The displaysubstrate according to claim 15, wherein a distance between the flatpart and the reflective layer is greater than or equal to a distancebetween the first slope part and the reflective layer; and the distancebetween the flat part and the reflective layer is greater than or equalto a distance between the second slope part and the reflective layer.20. The display substrate according to claim 15, wherein an intersectionof a tangent at a middle position of the first slope and a tangent at amiddle position of the second slope is on a side of the reflective layeraway from the base substrate.